Sorry for the delay, here's what I found:
Your modem apparently uses a smartlimk chipset. However, the smartlink drivers won't work out of the box:
Has a modified driver that supposedly works (the one with debug.tar.gz extension)
Has the instruction installation sheet.
Finally, this thread:
Is a walkthrough of a successful installation (please read entire thread)
Some of it is in Spanish, but none of the critical elements are.
Can't determine wether any of this will work for you, but it might be worth a try.
Please post results (I would suggest doing a backup and creating a rescue or boot disk just in case)